The deal will allow mobile operators to offer their customers a service that combines Napster's PC music downloads with Ericsson's mobile phone-based music service. The companies say it is the first fully integrated digital music service on offer.
It is due to go live in select European markets over the next 12 months and will also be offered in parts of Asia, Latin America and North America.
Napster said the service would work on current handsets, but can also accommodate next-generation technology for newer handsets on higher-speed networks. It is designed to work on mobile phones from all major manufacturers, and will be billed by the mobile operators.
Carl-Henric Svanberg, president and CEO of Ericsson, said: "With Napster we are uniquely positioned to deliver the easy-to-use, complete suite of music offerings our customers are asking for.
"We gain access to the strongest digital music brand in the world and exposure to the largest music catalogue available, which will not only increase our customer's consumer offerings and revenues but substantially strengthen their own brand image as well."
Mobile phone companies including O2 and T-Mobile are looking at music downloads as new revenue streams and record labels are keen to get in on the act to sell more music. The makers of handsets are also joining in, with Nokia unveiling a mobile phone it says will rival the iPod earlier this year.
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